Her body was was found at a property in Tailyour Road, Plymouth, on 14 December, Taunton Crown Court heard.

The court was read a letter from Ms Power's 10-year-old son Ollie in which he said Wilder had "ruined my life and my family's life".

Judge Graham Cottle said Wilder would have to serve at least 17-and-a-half years before being considered for parole.

You have ruined my life and my family's lifeOllie Power, Letter to David Wilder

The court heard that in the days before the killing, bus driver Wilder bombarded Ms Power with texts and phone calls, stalked her and turned up drunk at her house, but his demands for a reconciliation were rejected.

'Sad, miserable life'

The court heard Ollie said he had been disturbed in the middle of the night when he heard his mother making "'strange noises" and Wilder making "muttering noises".

Early the next morning he said he got up and found his mother lying dead under a duvet in the front room of the house with Wilder lying next to her.

The court was told that in 2009 Wilder had nearly killed his ex-wife Kelly in a similar attack.

The hearing was read out an extract of letter that Ollie had sent to Wilder in custody.

It said: "I feel very angry. If I was you I would ashamed. I have a sad, miserable life.

"You have ruined my life and my family's life. It was nearly Christmas and we were happy."

Senior investigating officer Det Insp Costa Nassaris welcomed the life sentence, saying the "selfish murder" had been "committed by a controlling and manipulative individual".

He added he wanted to pay tribute to Ms Power's family who had "conducted themselves with dignity and courage throughout", especially Ollie.